The invention relates generally to automatically operated devices to repeatedly dispense fluid material from a replaceable reservoir, and more particularly to a fluid dispensing apparatus and method that dispenses fluid material automatically in response to sensing the presence of a user.
Users of modem public washroom facilities increasingly desire that each of the fixtures in the washroom operate automatically without being touched by the user""s hands. This is important in view of increased user awareness of the degree to which germs and bacteria may be transmitted from one person to another in a public washroom environment. Today, it is not uncommon to find public washrooms with automatic, hands-free operated toilet and urinal units, hand washing faucets, soap dispensers, hand dryers and door opening mechanisms. This automation allows the user to avoid touching any of the fixtures in the facility, and therefore lessens the opportunity for the transmission of disease carrying germs or bacteria resulting from manual contact with the fixtures in the washroom.
It is also required that counter-mounted fluid soap dispensers in public washrooms include a soap reservoir that is readily replaceable when empty, and is inexpensive to manufacture and maintain. Therefore, it is desirable that the soap reservoir include a container that is easy to install in association with the permanent elements of the soap dispensing fixture, is held fast to the fixture, and is easy to remove from the fixture when empty, and functions in coordination with the operating elements of the fluid soap dispenser.
It is also desirable that a soap reservoir include a fluid soap delivery system that ensures the delivery of a uniform measured dose of fluid soap to a user upon each automatic actuation of the fixture. The reservoir and pump assembly must function as a unitary device to deliver consistent measures of fluid soap from the reservoir to the user.
Several automatically operated washroom fluid soap dispensers have been developed, as disclosed in U.S. Pat. No. 4,967,935 (Celest), U.S. Pat. No. 4,938,384 (Pilolla), U.S. Pat. No. 4,921,150 (Lagargren), U.S. Pat. No. 4,722,372 (Hoffman), and U.S. Pat. No. 4,645,094 (Acklin), by way of example. However, these devices do not incorporate structural elements that desirably provide consistent operation, ease of installation and replaceability, and low cost of manufacture.
The invention works towards overcoming the above problems in prior countertop fluid soap dispenser fixtures. The disclosed invention presents a fluid soap dispenser assembly that provides a consistent measured amount of fluid soap into the hands of a user. Towards this, an embodiment of the invention includes an elongated delivery tube directly connected to a reservoir container and pump assembly, which delivery tube moves axially within a rigid dispensing spout each time the fluid soap dispenser is actuated.
The soap delivery tube and pump assembly are centrally mounted on the top of a fluid soap reservoir container. As a result, a new delivery tube, pump assembly, and fluid soap container may be provided with a full soap reservoir assembly upon each replacement of an empty soap reservoir assembly. Moreover, as a result of the centrally disposed location of the elongated delivery tube and pump assembly on the reservoir container, the delivery tube may be readily extended axially through a curved, rigid dispensing spout mounted to the countertop, and the delivery tube may be readily rotated about its longitudinal axis for ease of movement in the dispensing spout when the unitary reservoir container, pump assembly and delivery tube assembly are rotated during installation of a new, full reservoir container and pump assembly.
The pump assembly mounted on the fluid soap reservoir of the invention also provides a pump actuator mechanism. The pump actuator mechanism may include a laterally extending actuator portion of the pump assembly. The actuator portion may permit the pump assembly and delivery tube to be mounted centrally with respect to the axis of the reservoir container and the soap dispenser fixture elements. The pump actuator mechanism is controlled by a battery operated or other power activated drive mechanism. The drive mechanism is activated upon the sensing of the presence of a user""s hand at a position that is adjacent to the dispensing spout. This may be achieved by a reflective proximity sensor forming part of the soap dispensing fixture mounted above the countertop.
The fluid soap reservoir container and pump assembly of the invention also provides advantages over fluid soap dispensing systems of the prior art. A standard manufactured pump assembly may be used in the fabrication of the reservoir module of the invention due to the central position of the pump and of the dispensing tube relative to the soap container. This permits the reservoir module to be filled using standard bottle filling equipment found in the facilities of most contract bottle fillers. This application of standard equipment provides a substantial cost savings in the production of soap refill reservoir modules in accordance with the invention.
The central location of the pump assembly and delivery spout on the reservoir module also permits rapid installation of the reservoir module on the motor housing of the dispenser by a simple rotation of the soap reservoir and pump assembly to complete a bayonet-type connection with the fixed pump housing of the invention. Moreover, the construction of the reservoir and pump assembly enables the mass production of a reliable refill unit.
The combination of the rigid dispensing spout and fluid soap delivery tube moveable inside the spout permits economy of construction not found in prior automatic soap dispensers. The spring in the pump assembly mounted on the soap container provides the force to return the delivery tube to its start position after a dose of fluid soap has been dispensed. The spout configuration and construction is adapted to provide ease of movement of the delivery tube in the spout, with a minimum of friction produced. The elongated delivery tube of the invention is rigid enough to withstand hydraulic pressure developed during the dispensing operation, and flexible enough to move substantially frictionless relative to the interior of the dispensing spout.
The motor housing of the invention mounts to a shank extending through a countertop, such that the housing may be readily rotated away from the underside of the sink bowl, and away from plumbing fixtures. This is a result of the central mounting of the operative components extending from the reservoir module, through the motor housing, to the entrance to the dispensing spout.
The invention also includes indicators to advise a maintenance operator when the reservoir module is empty of fluid soap after a predetermined number of electronically metered doses of soap have been dispensed. A separate indicator advises when the system""s batteries are low.